
\begingroup
\centering
\begin{tabular}{lcccc}
   \toprule
                                & (1)          & (2)          & (3)           & (4)\\  
   $\textbf{Ammonia (unfiltered)}$\\
   IHS restored wetland (acres) & -0.002$^{*}$ & -0.002$^{*}$ & 0.004$^{***}$ & 0.003$^{**}$\\   
                                & (0.001)      & (0.001)      & (0.002)       & (0.002)\\   
    \\
   Dependent variable mean      & 0.25687      & 0.24932      & 0.26084       & 0.25796\\  
   Observations                 & 264,952      & 221,117      & 25,090        & 23,920\\  
   Adjusted R$^2$               & 0.12202      & 0.13845      & 0.13422       & 0.13411\\  
\end{tabular}
\par\endgroup


